WereWeasel
CGN Regular
- Location
- Albert County, N.B
Hi all, I was curious if anyone had any success with the GMX projectile in their 1/14 barrels; I loaded some ammo .22-250 for a friend. He is a big fan of the 55gr VMAX, I just grabed a box of 55gr off the shelf that was mixed with the vmax and thought this was pricey stuff (50 for 35+tax); my bad but figured I'd make due.
The load I started with was
55gr GMX
37.5gr CFE223
Winchester FLS Brass
Federal LR Primer.
Which I figured would be close or a little faster that factory velocities of 3680fps.
He shot 3 of the 5 test rounds; they were all over the place, he had major pressure signs and one blown primer.
So I took apart one round to check the powder charge it was 37.5 bang on. I marked the test other round and set it aside. After googling reloading for GMX, I found out that some claim that the solid copper rounds produce higher pressures that lead and the starting charge is more mid range. So I loaded the next four with 36gr of CFE223 tossed in the orginal 37.5gr load and off to the range.
I shot a test group with my normal hand loads 5 shots@1" good enough for me, then moved on to the 55gr. loads. I loaded the mag being sure not to look so I had no idea where the original 37.5gr charge was. Fired all 5 rounds into a 7" group; inspected and measured all the brass from that sitting. Found no deviation other than the marker lines on the marked cases nor was there any added recoil, change in sound or hard ejection. Just poor grouping.
After my range tests I'm unclear why he had pressure signs at all but anyway back to the bullets. I know the .30cal crowd love them and the fast twist .22cal love the 70gr but what about the 55gr or even the 50gr any luck with GMX?
The load I started with was
55gr GMX
37.5gr CFE223
Winchester FLS Brass
Federal LR Primer.
Which I figured would be close or a little faster that factory velocities of 3680fps.
He shot 3 of the 5 test rounds; they were all over the place, he had major pressure signs and one blown primer.
So I took apart one round to check the powder charge it was 37.5 bang on. I marked the test other round and set it aside. After googling reloading for GMX, I found out that some claim that the solid copper rounds produce higher pressures that lead and the starting charge is more mid range. So I loaded the next four with 36gr of CFE223 tossed in the orginal 37.5gr load and off to the range.
I shot a test group with my normal hand loads 5 shots@1" good enough for me, then moved on to the 55gr. loads. I loaded the mag being sure not to look so I had no idea where the original 37.5gr charge was. Fired all 5 rounds into a 7" group; inspected and measured all the brass from that sitting. Found no deviation other than the marker lines on the marked cases nor was there any added recoil, change in sound or hard ejection. Just poor grouping.
After my range tests I'm unclear why he had pressure signs at all but anyway back to the bullets. I know the .30cal crowd love them and the fast twist .22cal love the 70gr but what about the 55gr or even the 50gr any luck with GMX?
